showing 13 related works from this author
Negatively Curved Nanographene with Heptagonal and [5]Helicene Units
2020
Negatively curved nanographene (NG) 4, having two heptagons and a [5]helicene, was unexpectedly obtained by aryl rearrangement and stepwise cyclodehydrogenations. X-ray crystallography confirmed the saddle-shaped structures of intermediate 3 and NG 4. The favorability of rearrangement over helicene formation following radical cation or arenium cation mechanisms is supported by theoretical calculations. NG 4 demonstrates a reversible mechanochromic color change and solid-state emission, presumably benefiting from its loose crystal packing. After resolution by chiral high-performance liquid chromatography, the circular dichroism spectra of enantiomers 4-(P) and 4-(M) were measured and showed …
Amplification of Dissymmetry Factors in π-Extended [7]- and [9]Helicenes
2021
International audience; $\pi$-Extended helicenes constitute an important class of polycyclic aromatic hydrocarbons with intrinsic chirality. Herein, we report the syntheses of $\pi$extended [7]helicene $4$ and $\pi$-extended [9]helicene $6$ through regioselective cyclodehydrogenation in high yields, where a "prefusion" strategy plays a key role in preventing undesirable aryl rearrangements. The unique helical structures are unambiguously confirmed by X-ray crystal structure analysis. Compared to the parent pristine [7]helicene and [9]helicene, these novel $\pi$-extended helicenes display significantly improved photophysical properties, with a quantum yield of 0.41 for $6$. After optical res…
From Hexaphenylbenzene to 1,2,3,4,5,6-Hexacyclohexylcyclohexane
2020
The hydrogenation of hexaphenylbenzene was studied, affording novel partially hydrogenated hexacyclohexylbenzene (HCB) as well as fully hydrogenated 1,2,3,4,5,6-hexacyclohexylcyclohexane (HCC) as an unprecedented “oligocyclohexyl” molecule. The reaction process was analyzed by mass spectrometry with atmospheric pressure chemical ionization and high-performance liquid chromatography. From a crude product mixture, two different crystals with flake- and block-shapes could be grown and analyzed by X-ray crystallography, revealing their structures as HCB and HCC. While a geared arrangement of cyclohexyl substitutes was found in HCB, two isomeric structures were identified in HCC crystal with cha…
A Highly Luminescent Nitrogen-Doped Nanographene as an Acid- and Metal-Sensitive Fluorophore for Optical Imaging.
2021
Dibenzo[hi,st]ovalene (DBOV) has excellent photophysical properties, including strong fluorescence and high ambient stability. Moreover, the optical blinking properties of DBOV have enabled optical super-resolution single-molecule localization microscopy with an imaging resolution beyond the diffraction limit. Various organic and inorganic fluorescent probes have been developed for super-resolution imaging, but those sensitive to pH and/or metal ions have remained elusive. Here, we report a diaza-derivative of DBOV (N-DBOV), synthesized in eight steps with a total yield of 15%. Nitrogen (N)-bearing zigzag edges were formed through oxidative cyclization of amino groups in the last step. UV-v…
CCDC 2047542: Experimental Crystal Structure Determination
2021
Related Article: Zijie Qiu, Cheng-Wei Ju, Lucas Frédéric, Yunbin Hu, Dieter Schollmeyer, Grégory Pieters, Klaus Müllen, Akimitsu Narita|2021|J.Am.Chem.Soc.|143|4661|doi:10.1021/jacs.0c13197
CCDC 2004421: Experimental Crystal Structure Determination
2020
Related Article: Zijie Qiu, Sobi Asako, Yunbin Hu, Cheng-Wei Ju, Thomas Liu, Loïc Rondin, Dieter Schollmeyer, Jean-Sébastien Lauret, Klaus Müllen, Akimitsu Narita|2020|J.Am.Chem.Soc.|142|14814|doi:10.1021/jacs.0c05504
CCDC 2021692: Experimental Crystal Structure Determination
2020
Related Article: Zijie Qiu, Sobi Asako, Yunbin Hu, Cheng-Wei Ju, Thomas Liu, Loïc Rondin, Dieter Schollmeyer, Jean-Sébastien Lauret, Klaus Müllen, Akimitsu Narita|2020|J.Am.Chem.Soc.|142|14814|doi:10.1021/jacs.0c05504
CCDC 2047540: Experimental Crystal Structure Determination
2021
Related Article: Zijie Qiu, Cheng-Wei Ju, Lucas Frédéric, Yunbin Hu, Dieter Schollmeyer, Grégory Pieters, Klaus Müllen, Akimitsu Narita|2021|J.Am.Chem.Soc.|143|4661|doi:10.1021/jacs.0c13197
CCDC 2004419: Experimental Crystal Structure Determination
2020
Related Article: Zijie Qiu, Sobi Asako, Yunbin Hu, Cheng-Wei Ju, Thomas Liu, Loïc Rondin, Dieter Schollmeyer, Jean-Sébastien Lauret, Klaus Müllen, Akimitsu Narita|2020|J.Am.Chem.Soc.|142|14814|doi:10.1021/jacs.0c05504
CCDC 2047541: Experimental Crystal Structure Determination
2021
Related Article: Zijie Qiu, Cheng-Wei Ju, Lucas Frédéric, Yunbin Hu, Dieter Schollmeyer, Grégory Pieters, Klaus Müllen, Akimitsu Narita|2021|J.Am.Chem.Soc.|143|4661|doi:10.1021/jacs.0c13197
CCDC 2000869: Experimental Crystal Structure Determination
2020
Related Article: Marcel Dillenburger, Zijie Qiu, Cheng-Wei Ju, Beate Müller, Svenja Morsbach, Dieter Schollmeyer, Akimitsu Narita, Klaus Müllen|2020|J.Am.Chem.Soc.|142|12916|doi:10.1021/jacs.0c04956
CCDC 2004420: Experimental Crystal Structure Determination
2020
Related Article: Zijie Qiu, Sobi Asako, Yunbin Hu, Cheng-Wei Ju, Thomas Liu, Loïc Rondin, Dieter Schollmeyer, Jean-Sébastien Lauret, Klaus Müllen, Akimitsu Narita|2020|J.Am.Chem.Soc.|142|14814|doi:10.1021/jacs.0c05504
CCDC 2000868: Experimental Crystal Structure Determination
2020
Related Article: Marcel Dillenburger, Zijie Qiu, Cheng-Wei Ju, Beate Müller, Svenja Morsbach, Dieter Schollmeyer, Akimitsu Narita, Klaus Müllen|2020|J.Am.Chem.Soc.|142|12916|doi:10.1021/jacs.0c04956